5-羟甲基胞嘧啶:早期检测消化系肿瘤的新标志物?

5-hydroxymethylcytosine:A new marker for early detection of digestive system tumors?

哺乳动物基因组DNA上5-甲基胞嘧(5-methylcytosine,5-mc)中是一种常见的表观遗传修饰.随后的研究发现10-11易位蛋白(Ten-Eleven-Translocation protein,TET蛋白)家族可将5-mc氧化成5-羟甲基胞嘧啶(5-hydroxymethylcytosine,5-hmc),即基因组的第六碱基.最近研究发现在消化系肿瘤中可发现5-hmc水平的降低,提示5-hmc可能是一个早期检测消化系肿瘤的表观遗传标志物.为了更好地了解5-hmc和TET的作用,本文对TET蛋白的功能和5-hmc与消化系肿瘤的关系进行了如下阐述.

5-methylcytosine （5-mc） has been recognizedas an important epigenetic modification in mammalian genomic DNA. Studies have revealed that TET （ten-eleven translocation） protein family could catalyze the conversion of 5-mc into 5-hydroxyme-thylcytosine （5-hmc）, which is now widely recognized as the sixth base in the genome. Recent reports showed that the level of 5-hmc was decreased in digestive system tumors, indicating that 5-hrnc may be a useful epigenetic biomarker for the early diagnosis of gastrointestinal tumors. To better understand the roles of TET and 5-hmc, this article will elucidate the function of TET protein and the connections between 5-hmc and digestive system tumors.